Does Lightning Cause Migraines?

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Lightning strikes may trigger migraine headaches, according to
new research.

The findings, published today (Jan. 24) in the journal
Cephalalgia, are correlational, so they can't show that
lightning strikes close to a person's house actually cause
the headaches. But the changes in the air around a lightning
strike could conceivably trigger electrical changes in the brains
of migraine sufferers and cause headaches, said Frederick
Freitag, the director of the headache center at Baylor University
Medical Center in Dallas, who was not involved in the study.

Vincent Martin, a headache specialist at the University of
Cincinnati, noticed that thunderstorms seemed to spur migraine
headaches in some of his patients.

Intrigued, Martin and his colleagues wondered whether the effect
was all in patients' heads or not.

To find out, he looked at data from a separate study of 90
migraine sufferers, more than 90 percent of them women, from the
St. Louis and Cincinnati areas who had kept a daily diary of all
their potential triggers for three to six months.

"When a thunderstorm rolls in, there could be 50,000 lightning
strikes within 25 miles [40 kilometers] of your house, you just
don't realize it," Martin told LiveScience.

Patients were 30 percent more likely to get a migraine headache
and 28 percent more likely to get a general headache on
lightning-strike days, the team found.

After controlling for other aspects of the thunderstorms that
could cause headaches – such as temperature, barometric pressure,
wind, humidity and rain – they linked lightning to a 13 percent
jump in the likelihood of an attack.

Though the study can't prove that lightning actually triggered
the migraine headaches, there are multiple ways in which it
theoretically could, Martin said.

When lightning hits the ground, it creates low-frequency
electromagnetic waves that induce a
magnetic field, which could change the electrical signals in
the brain, he said. Lightning also increases the number of
positively charged ions in the air. And the electrical strikes
also increase the concentration of the irritant ozone in the air.

Freitag said that though it may sound far-fetched, thunderstorms,
via changes in the air's ionic charge, could trigger
migraines.

For instance, research has shown barometric pressure can change
concentrations in the air, which, in turn, can cause the release
of the
brain chemical serotonin, Freitag told LiveScience. Serotonin
release can cause pain, he said.

But migraine frequency isn't constant, so the research team would
need to study a geographic region that's broader, and for more
time, to really pin down the link between headaches and
lightning, Freitag said.